Nut-tapping machine.



H. CREHAN.

NUT TAPPI'NG MACHINE. APPLICATION FILED MAY 27. 1914.

Patented Aug. 10, 1915.

6 SHEETS-SHEET I.

INVENTOR W- Gal/4.4. 7

WITNESSES 51.74 W

ATTOR N EYS H. CREHAN.

NUT TAPPING MACHINE.

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INVENTQR WM 825% WITNESSES ATTOR NEYa H. CREHAN;

NUT TAPPING MACHINE.

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ATTORNEYS Patente Aug. 10, 1915.

6 SHEETS SHEET 4.

ATTORNEYS INVENTOR- H. CREHAN.

NUT TAPPING MACHINE.

APPLICATION man mvzz, 19m.

3mm an 'H. CREHAN.

NUT TAPPING MACHINE.

APPLICATION FILED MAY 21. 1914.

Patented Aug. 10,1915;

6 SHEETS-SHEE'I 5.

N M WITNESSES INVENTOR 1,; ATTOF-INEYB H. CREHAN;

NUT TAPPING MACHINE.

v APPLICATION FILED mwzz. m4. 1 9,553, Patented Aug. 10, 1915.

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HUBEBT CREHAN, F PITTSBURGH, PENNSYLVANIA.

NUT TAZPPING MACHINE.

Specification of Letters Patent.

Patented Aug. 10, 1915.

Application filed May 27, 1914. Serial No. 841,247.

Machines, of which the following is a full,

- clear, and exact description, reference being had to the accompanying drawings, in which a Figure 1 is a planfview of my improved apparatus; Fig. 2 is a side elevation; Fig. 3

is an end elevation, the hopper being removed; Fig. 4 is a view partly in section, showing the reversing screw; Fig. 5 is a like view showing the lead screw; Fig. 6

is an enlarged view of the tapping chuclc in operative position for tapping the nut;

Fig. 7 is a sectional view of the tap chuck;

- Fig. 8 is a sectional view of the tap chuck,

the parts being in the position assumed when the tap meets an obstruction; Fig. 9 is an end view of the nut feeding mechanism; Fig. 10 is a sideelevation of the nut feeding mechanism; Fig. 11 is a horizontal sectional view of the hopper and portion of the feed mechanism on the line 1111 of Fi 9; Fig. 12 is a vertical sectional view line 1212 of Fig.'11; Fig. 13 is b on the detached elevation of one of the feeding arms; Fig. 14 is a plan View of the same; Fig. 15 is a vertical sectional View on the line 15-15 of Fig. 13; Fig. 16 is a detached end elevation of the block which closes the end of the openings in the hopper in which the feeding arm acts; and Fig. 17 is a detached side elevation of the same.

My invention relates to that class of apparatus for automatically tapping or threading nuts in which the nuts. are fed continuously and automatically from a hopper v to a matrix where they are successively subwhich may be mounted or fixed to any suitjected to the rotary tap,

action of a reciprocating and and it consists in mechanlsm i for operating and automaticaly reversing the movement of the tap and for feeding the blanks -to and releasing thethreaded nut from the matrix; it also consists in mechanism by means of which power is applied to a series of taps from a common source,

in safety devices to prevent the clogging and breaking of the operative parts, and in mechanism embodied in the severalparts as is hereinafter more fully described.

In the drawing 2 represents the central power shaft supported by the housings 3 able bed plate. Keyed to the shaft 2 is the band wheel 4, on each side of which and loosely mounted on the shaft 2 arethe band -wheels 5, 5. Embracing these band wheels are two belts, one of which is crossed, which belts pass over band wheels on a power shaft, which, as well as the belts, are not shown in the drawing. Mounted on the bed plate are two standards 28 in the upper portions of which are slots through which passes the sliding bar 25; the bar resting on anti-friction wheels 29. Keyed to the slidlng bar 25 are two belt guides 26 having slots through which pass the belts that drive the wheel 4. By means of these belt guides the 'two belts may be shifted from either of the loose band wheels 5 tothe keyed band wheel 4 by the movement of the bar 25, whlch movement is produced by the lever 22 at the upper end of which is a weight 23 and in which is a slot and pin connection 24 which connects the lever 22 with the bar 25. This lever 22 is keyed at its lower end to the rock, shaft 22. The movement of the bar 25 is limited by the stops 27, 27, which come in contact with the standards 28.

Keyed to the shaft 2 is awide gear wheel *6 which meshes with the gear wheels 7, 7

which are keyed to the shafts 8, 8. Mounted on the shafts 8 are threaded sleeves 9 which are secured to the shafts 8 by the pins 10. The shafts 8 are mounted in the bearings 8 8 and threaded bearing 9' which is fitted in the standard 8', the thread of which engages with the screw of the sleeve 9. At each end of the shafts 18 are tap carrying chucks 11.. Keyed to one of the shafts 8 is the wide gear wheel 14 which meshes with a gear wheel 15 which is keyed to one end of a reversing screw 16 constituting a reversing shaft, the thread of which engages with the interior threads ofthe blocks 17 17 which are slidably mounted on the slide bar 17 and on which the blocks 17 are caused to travel by the rotation of the screw 16. This bar 17 is detachably connected be turned on the thread 16 to bring them closer together or farther apart and thus shorten or lengthen the reversing movement of the apparatus. Between'the blocks 17 ,17

'is the rocking lever 18 which is keyed to the over, thus giving a partial rotation to the shaft 19 which in turn moves the levers 20, 21, arm. 22, and bar 25, thus shifting the belt guides 26, 26 onthe band wheels 5, 4 and 5, this movement being assisted by the weight 23 at the end of the arm 22, whereby the movement-of the main power shaft 2 is reversed. The rotation of the shaft. 8 and threaded sleeve 9' causes the shaft 8 to move longitudinally; first forwardly to carry the tap 12 through the cavity in the nut and then, as the mechanism is reversed as just described, backwardly to withdraw the tap. The chuck 11 which carries the tapping bit 12 in the removable bushing 37 is in the form of a sleeve which fits on the ends of the shafts 8 and is secured thereon by means of the pin 32 fitting in the slot 32 and also by the lugs 33 having inclined end faces -which seat in the V-shaped cavities 34 in the shaft 8, the lugs 33 being normally held in position by the leaf springs 35. The purpose of this connection between the chuck 11 and the shaft 8 is to permit the chuck 11 to slide backwardly on the shaft should the bit 12 encounter an obstruction, the excessive pressure of which on the bit being eX- erted on the chuck causes the lugs 33 to slip out of the cavities 34, allowing the chuck to slide back on the shaft 8, the pin 32 moving in the slot 32'. The leaf springs 35 are secured to the chuck 11 by means of the bolts 38, and the springs are held in position by the pins 36 fitted in cavities formed in the chuck. The purpose ofthe gear wheels 6 and 14 being wide is to permit of the reciprocatory movement of the gearwheels 7 and 14, which are. keyed to the shaft 8, without losing mesh with the gear wheels 15 and 6; Owing to this arrangement of a central power shaft with two tapping shafts, it is possible to place four taps on one bed plate; one at each end of the two shafts 8, which are arranged on both sides of the central shaft 2; the only difference between the mechanism on one side from that on the other being that on one is the reversing mechanism 'which reverses the movement of the shaft 2, which mechanism is not duplicated on the other side of the apparatus.

The nut feeding mechanism is composed of a hopper, feeding arms and actuating mechanism,"and a chute which leads fromthe hopper to the matrix in which the nuts are tapped. In the drawings 60 represents the hopper, which is secured to the vertical plate 60' of the frame of the apparatus by bolts passing through the lug 70, and the block pieces 66, and is otherwise removed from the face of the plate 60 sufiiciently to form a slot in which the rocking arms or feeders 59 move; the space between the curved faces of the two rockers being closed by the projecting rib 69 which is of the same thickness as the rocking arms. These rocking arms 59 are keyed to short shafts58 by keys 59, the shafts 58" being journaled in journal bearings extending from the plate 60. 1n the upper face of therocking arms 59 aregrooves 61' of such shape and size as to hold the nut vertically when the arms are raised; the inner portion of the groove terminating in an abrupt upwardly extending curve, the upper corner of which is rounded to prevent the lodgment of the nut thereon. At the upper ortion of the projecting rib 69 are shoul ers 69 which serve as stops to the upward movement of the rocking arms 59. In rear of the pivoted ends of the arms 59 are filling blocks 66 which close the space at this point between the hopper and the face of the plate 60, the purpose being to prevent the escape of the nuts contained in the hopper when the free end of the arm 59 is raised. Pivoted to the plate 60 above the delivery portion of the groove 61 is a swinging arm 71 which is pivoted on a pintle or rod 72, the lower end of the arm extending down into the path of the nuts moving in the groove. 'When the chute, intowhich the nuts are delivered, is full so that no more nuts can be delivered therein,the rear end of the swinging arm 71 strikes against the last nut delivered, and is thus prevented from being swung aside to permit the passage of other nuts from crowding into the chute in the wrong position. Leading from the end of the groove 61, adjacent to the pivoted point of the arm 59, is a vertical chute 62 which carries the nuts from the hopper to the ma trix in which the nuts are tapped. Keyed to the short shafts 58 are the arms 58, to the outer ends of which are. pivoted the toggle lever arms 57, the inner. ends of which arms 57 are povited' or toggled tothe vertical rod 56 to which is keyed a collar 55 and on which is a sliding washer 53. Between the washer 53 and the collar 55 is a coil spring 54. The lower portion of the arm '56 passes through and is guided in its movement by'a'n opening in the bed plate of the apparatus.

J ournaled in journals 5.1 on the bed plate of the apparatus is a longitudinal shaft 50 driven by a belt wheel 49. Keyedto the shaft 50 is a cam 52 on which rests alever arm 53 which is pivoted to a standard extending from the bed plate. The outer end of this arm 53 is slotted to ermit the passage of the rod 56; the portions of the arm on each side of the slot bearing against the washer 53. By rotation of the shaft .50 the cam 52 is caused to raise and lower the arm 53 which raises and lowers the rod 56, thus operating the toggle arms 57 and through the connecting mechanism the feeding arms 59 which causes the arms 59 to rise in the hopper 60 to the position shown in dotted lines in Fig. 9, a certain number of nuts being engaged and lifted in the groove 61 which, when the arms 59 arein their elevated position, form inclined ways leading into the chutes 62. 'The'purpose of the spring 54 is to impart a yielding movement to the rod 56. Extending from the fillin blocks 66 are curved projections 68 whic it over the rounded end of the arm sponds to the shape of the nut allowing the nuts'to fall to the lower end of the chute without clogging. In the side of the chutes,

' near the lower ends thereof, are openings 63 through which bolts or pins may be inserted v to block or stop the passage of the nuts through the chutes. At the ends of the' chutes 62 are sliding plates 46 which'normally close the bottom 0 ening of the chutes p 62; the plate beingihel in its closed position by the springs 48 and. 48', and extending downwardly from the plate 46 is an arm 46 in the path of a pushing rod 42 which is carried by a sleeve 43 *which is supported by the standards 45 and 34',one end of the pushing'rod being secured to the hangin arm 41, the upper end ofwhich is provide with a journal which fits loosely on the shaft 8 between the ear wheel 7, and a-collar' 39 which is keye to the shaft, whereby the shaft 8 rotates freely in the journal of the ar'm141 and yet carries. the arm 41 with the reciprocating movement of the shaft, thus causing the rod 42 to press the arm 46'- against the force of the springs 48 and 48', moving the plate 46 from' beneath the chute 62 with the movement of the bit 12. This allows the nut previously tapped by the bit 12 to'drop from the'bottom of the chute. It

by the inthe 0 will be noted that the matrix in which the nut is tapped, is formed by the sides of the chute, by a nut which has passed in the chute below the tapping bit 12, and is supported late 46, and by the column of nuts hute 62. The operation of my device is as followsz-The blank nuts being fed into the hopper 60, and power ap lied tothe shaft 50 through theband whee 49, the cams 52 at each end of the apparatus lift the lever arms 53 which operates the vertical rods 56, the toggles 57, 58, and'raise and lower the feeding arms 59 which feed the blank nuts into' the chutes 62. When the chutes are filledthe swinging arm 71 coming incontact with theuppermost nuts in the chutes prevent any more from entering; the action of the arms 59 thereafter resulting in merely tumbling the blanks in the hopper. When the chutes have thus been supplied with blanks, power is applied to the beltsleading to the beltwheel 4'which imparts motion to the central shaft 2 caus ing the gear wheels 6 and 7 to rotate, thus imparting a rotary movement to the two shafts 8, 8, and, as the shafts rotate in the threaded box 9, they are caused to move forwardly atone end of the apparatus, the tap 12 entering the opening 64 of the matrix tapping the nuts contained therein. -As the gear wheel 14 revolves it imparts movement to the gear wheel 15 and threaded shaft 16 p which, as the shaft is held from longitudinal movement, imparts motion to the threaded blocks 17, 17, andas the tapping operation is completed one of the blocks 17 comes in contactwith the lever arm 18 throwing it (v I over and reversing the movement of the shaft 2 by shifting the belts on the wheels "5 and 4, this being accomplished by means of the lever arms connecting the shaft 19 with the sliding rod 25, and thereupon the taps 12 which have completed their tapping operation. are withdrawn while the tapping dies 12 at the'other end of-the apparatus been described. The rod 42 being'connected with the ban er 41 o'n'the shaft 8 moves forward with t e shaft and pushes back the sliding plate 46 releasing the nut at thev serves to support the next-succeedin blank and holds it in position'to be'tappe I on the return of the tape Among the advantages of' my invention which may be appreciated by those skilled aremoved forward in a like manner as has in the art, is the simplicity of the apparatus'which requires a minimum of power and allows-positive and rapid operation of the parts, thus enabling the nuts to be tapped rapidly and at small ex use.

What I claim and desire to secureby Letters Patent is:

1. In an automatic nut tapping machine,

the combination of a main shaft having reversible driving mechanism, a rotaryre ciprocating tapping shaft, a rotary reversing shafthaving a threaded portion, threaded sto blocks carried by said reversing shaft an adapted to be reciprocated by the rotation thereof, and devices adapted to be operated by the blocks and connected with the reversing mechanism.

2. In an automatic nut tapping machine,

the combination of a main shaft having reversible driving mechanism, a rotary reciprocating tapping shaft, a rotary reversing shaft having a threaded portion, threaded stop. blocks carried by said reversing shaft and adapted to be reciprocated by the rotation thereof, said blocks being adjustable upon said reversing shaft 'to regulate the relative position of said blocks thereon, and means for maintaining said blocks in adjustable position, and devices adapted to be operated by the blocks and connected with the reversing mechanism.

3. In an automatic nut tapping machine, the combination of a mainshaft having reversible driving mechanism reversing mechanism therefor, a rotary reciprocating tapping shaft, broad and narrow gears in mesh and carried respectively by' saidshafts, a thread fixed on the tapping shaft and engaging with a fixed threaded bearing, and

means controlled by the tapping shaft for automatically actuating said reversing mechanism at each end of its travel.

4. In an automatic tapping machine, the combination of a main shaft having reversible driving mechanism, a rotary reciprocatr ing tapping shaft, a rotary reversing shaft, means connecting the main and the tapping shafts, and means connecting the tapping and the reversing shafts, each means comprising a broad gear on one shaft'and a narrow gear on the other shaft in mesh therewith, and reversing mechanism actuated by said broad and narrow gears and.

connecting the tapping and reversing shafts.

5. In an automatic nut tapping machine, the combination of a rotary reciprocating tapping shaft, a reversing shaft, a thread on the reversing shaft, reciprocating threaded blocks engaging with the thread of the reversing shaft, a rocking lever situated in the ath of the blocks, and mechanism connecting the rock lever with the reversing mechanism. I

6. In an automatic nut tapping machine, the combination of a main shaft having reversing mechanism, a threaded tapping shaft, a threaded bearing in' which the tapping shaft is journaled, a power communicating device fixed to the main shaft, a power communicating device fixed to the tapping shaft adapted to reciprocate.there-' with and engaging directly with the powercommunicating device of the main shaft, and mechanism continuously actuated by the tapping shaft'for automatically causing an intermittent -action of the reversing mechanism and a consequent reversal 'of the direction of rotation of said shaftat each end of its travel.

In testimony whereof, I have hereunto set my hand.

HUBERT CREHAN. Witnesses:

T. -B. HUMPHRms, JAMES K. BAKEWELL. 

